The evaluation of possible bacterial virulence factors for E. coli strains causing urinary tract infections (UTI) will be performed. Smooth wild strains of E. coli obtained from patients with UTIs will be characterized for its possession or lack of the following properties: 1) smooth or rough lipopolysaccharide (LPS); 2) homolysins; 3) P-fimbriae; 4) type 1 fimbriae; 5) type X and M adhesins; 6) capsular polysaccharide and type (which most likely is strongly correlated with bactericidal resistance); 7) presence of flagella; and 8) moreover each bacteria used will be characterized for their biochemical patterns, LPS, fimbrial subunit and outer membrane protein profiles on SDS polyacrylamide gel electrophoresis (SDS-PAGE), plasmid content and antibiotic resistance pattern. In the most frequently occurring bacteria in upper UTI, molecular biological studies will be performed to gain basic knowledge of the structures of the different E. coli O-antigenic specific polysaccharides. Later biologically isolated relevant oligosaccharide fragments will be used in diagnosis, as well as in preparation of artificial vaccines. The pathophysiology of urinary tract infection will be studied in two animal species, the monkey (Macaca fascicularis) and inbred BALB/c mice using different bacterial strains with different combinations of virulence factors. Efforts will be made to elucidate the presence of common antigenic epitopes combined within the subunits of different P-fimbriae. Such peptide sequences, if present, will be used for diagnostic purposes such as measurement of protective antibody, and for use as haptens in the construction of artificial vaccines which will be tested in the monkey model. An attempt at modulating renal damage from acute pyelonephritis will be tested in the experimental monkey model by using anti-bacterial therapy with and without various anti-inflammatory agents. Patients will be followed for levels of serum antibody to the O-antigen as well as P-fimbrial antigen. If recurrent disease occurs, the level of such antibodies may be important.